Filter bags can be made from a variety of materials (also known as filter media), depending on the specific application, operating conditions of a baghouse,  and the type of contaminants or particles they are designed to capture. The following aspects must be considered when it comes to filter media design and selection:

• Verimlilik: Filtration efficiency, measured as the percentage of contaminants removed from the gas stream, is a crucial performance factor. Filter media captures particles through size exclusion, using their porous structure to physically block particles, or through adsorption and attraction mechanisms. Achieving high efficiency requires optimizing pore size, surface area, compatibility with the gas stream, and other filter media characteristics.
• Longevity and Durability: The operational lifespan of filter media depends on its resistance to factors causing degradation over time, including temperature, chemical exposure, moisture, and mechanical forces during cleaning/backwashing.
• Flexibility and Adaptability: The ability to adapt filter media to different applications through tailored pore sizes, compatibility with various chemistries, and configurations (depth vs surface filtration) expands its usefulness across industries. Media flexibility minimizes the need for custom media for specific applications, improving cost-effectiveness.

Overall, balancing these parameters can optimize filter operation, reduce operating costs over time, and minimize ecological impact – the core goals of high-performance and high-efficiency filtration. Careful media design and selection are key to achieving efficient, reliable, and environmentally sound dust emission controls. The filtration function of filter media is mainly determined by:

• Filtre Malzemesi
• Filtre Malzemesi Yapısı
• Filtre Ortamı Arıtımı

Filtre Malzemesi

Each material has its own unique filtration characteristics. Choosing the right material with its corresponding characteristics that are best suited for the specific application can help boost the performance and longevity of the dust filtration system.

Material Comparison

The table below is a filtration characteristics comparison across some of the most common filter media materials:

Filtre Ortamı	Sıcaklık Dayanımı	Chemical Compatibility	Aşınma Direnci	Moisture Resistance	Particle Size Range	Uygulama
Polyester	Up to 275°F (135°C)	İyi	Orta düzeyde	İyi	General	General industrial dust collection
Akrilik	Up to 275°F (135°C)	İyi	Orta düzeyde	İyi	Fine to Coarse	General industrial applications
PPS (Ryton)	Up to 375°F (190°C)	Mükemmel	Mükemmel	İyi	Fine to Medium	Coal-fired boilers, chemical plants
Aramid (Nomex)	Up to 400°F (204°C)	İyi	İyi	İyi	Fine to Medium	Asphalt production, metal smelting
P84 (Polyimide)	Up to 500°F (260°C)	Mükemmel	Mükemmel	İyi	Fine to Medium	Incineration, cement production
Fiberglas	Up to 500°F (260°C)	İyi	Mükemmel	Mükemmel	Fine to Coarse	High-temperature applications, metals
PTFE	Up to 500°F (260°C)	Mükemmel	Mükemmel	Mükemmel	Fine to Ultrafine	Chemical processing, pharmaceuticals

Note: The information provided in the table is general and may vary based on specific formulations and manufacturers. It’s important to consult with filter media suppliers and manufacturers for detailed specifications and recommendations based on particular requirements.

Material Selection Considerations

Selecting the right filter media for a baghouse is crucial for the effective and efficient operation of the dust collection system. Several factors should be considered when choosing filter media for a baghouse:

1. Particle Size and Characteristics: Identify the size and nature of the particles you need to capture. Different filter media are designed to handle specific particle sizes and types. For example, fine particulate matter may require a different filter media than larger, heavier particles.
2. Filtration Efficiency: Filtration efficiency is a measure of how well a baghouse filter bag can capture dust particles from a gas stream. It is usually expressed as a percentage of the inlet dust concentration that is removed by the filter bag.
3. Temperature: Consider the operating temperature of the process. Some filter media can withstand higher temperatures than others. If the process involves elevated temperatures, choose a filter media that can handle the heat without compromising performance.
4. Chemical Compatibility: Understand the chemical composition of the dust or particulate matter. Choose a filter media that is chemically compatible with the contaminants to prevent degradation or breakdown of the filter material.
5. Moisture Levels: Assess the moisture content in the gas stream. Some filter media may be prone to clogging or degradation when exposed to high levels of moisture. Select a filter media that can handle the moisture conditions of the application.
6. Abrasion Resistance: Consider the potential for abrasion in the gas stream. If the dust particles are abrasive, choose a filter media that is resistant to wear and tear to ensure a longer lifespan for the filter bags.
7. Cleaning Mechanism: Consider the cleaning method used in the baghouse (e.g., pulse jet cleaning, reverse air cleaning, shaker cleaning). Different filter media may respond differently to cleaning mechanisms, so choose a media that is compatible with the cleaning process.
8. Regulatory Compliance: Ensure that the selected filter media comply with any applicable regulatory standards and environmental requirements. Certain industries may have specific regulations regarding emissions and air quality, and using compliant filter media is essential.
9. Cost Considerations: Evaluate the initial cost and lifecycle cost of the filter media. While certain materials may be more expensive upfront, they could provide cost savings over the long term by offering better durability, performance, and lower maintenance costs.

Filtre Malzemesi Yapısı

Filtre ortamı yapısı, filtre ortamının inşa edilme şeklini ifade eder. Genellikle dokuma ve dokuma olmayan olarak kategorize edilir. Filtrasyon verimliliğini ve filtre torbası dayanıklılığını daha da artırmak için, filtre medyasını oluşturmak için genellikle çift yoğunluklu keçe yapısı kullanılır.

Nonwoven

Nonwoven fabrics are made using a process that involves first joining the fibers together in ordered or random patterns, and then coupling the layers of nonwoven with a polymer to give life to a porous material suitable for filtration. The most commonly used filtration nonwoven raw materials include polyester, acrylic, PPS, aramid, polymide, PTFE, fiberglass, and mixed fiber blends. Generally, they are used with higher energy cleaning systems such as pulse-jet dust collectors. The four most widely used nonwoven fabrication processes are:

• İğneleme
• Spunlace (Hidro-entangling)
• Spunbond
• Meltblown

İğne keçeleme kategorisinde, filtre medyası oluşturmak için genellikle çift yoğunluklu bir keçe yapısı kullanılır. Gerçek bir çift yoğunluklu filtre medyasında, farklı yoğunluktaki iki medya, ortada boyutsal stabilite sağlayan bir bez ve keçeden toz geçişini en aza indirerek filtrasyon verimliliğini artıran yoğunlaştırılmış bir merkezi çekirdek ile ayrılır. Bez yapısı, homojen bir elyaf karışımı ve sadece filtrasyon özellikleri ile tek bir işlemde üretilen desteksiz keçelere (bezsiz) göre açık bir avantaj sunar.

https://www.youtube.com/watch?v=eDvu1J48DFM&ab_channel=Groz-Beckert

Dokuma

Dokuma kumaşlar, monofilament veya fibrile iplikler gibi malzemelerin tek ipliklerinin bir dokuma tezgahında belirli bir tekrarlanan desenle dokunmasıyla yapılır. En yaygın kullanılan filtrasyon dokuma hammaddeleri polyester ve fiberglası içerir. Genellikle çalkalayıcı veya ters hava torbalı sistemler gibi düşük enerjili temizleme sistemleri ile kullanılırlar.

Filtre Ortamı Arıtımı

Farklı elyaflar her bir medyaya farklı toz filtreleme özellikleri sağlar. Filtre medyası, filtre medyası ömrünün uzatılması, daha iyi toz keki salınımı, daha az valf titreşimi, daha tutarlı hava akışı, daha düşük diferansiyel basınç ve daha az arıza süresi ve bakım gibi filtrasyon verimliliğini ve performansını iyileştirmek için daha fazla işlenebilir.

Singeing

Singeing is done by passing the filter material over an open flame. This removes any straggly surface fibers and results in a more uniform filter bag surface.  You can typically see this process done on polyester, polypropylene, acrylic, aramid, aramid, and P84 felts.

Kalenderleme (Camlama)

Calendering, also known as Glazing, is the high-pressure pressing of the fabric by rollers to flatten or smooth the material. Calendering pushes the surface fibers down onto the body of the filter media.  Calendering can be applied to various media such as polyester, polypropylene, and aramid. This is done to increase and uniform surface life, improve stability and reduce shrinkage.

Napping

This process is the scraping of the filter surface across metal points or burrs on a revolving cylinder. Napping raises the surface fibers, creating a “fuzz”, that provides a large number of sites for particle collection by interception and diffusion. Fabrics used for collecting sticky or oily dust are sometimes napped so they can provide better collection and an easier cleaning process.

Kaplama

Coating, also known as resin treatment, involves immersing the filter media in natural or synthetic resin. This process helps lubricate the fibers, helps the fibers to shed water and oils (hydrophobic & oleaphobic), and provides high-temperature durability.

ePTFE Membran

ePTFE, genişletilmiş politetrafloroetilen anlamına gelir ve filtrasyon performansını artırmak için filtre ortamının filtrasyon tarafına lamine edilen mikro gözenekli bir membrandır. Performans iyileştirmeleri arasında gelişmiş emisyon kontrolü, temizleme döngüsü sırasında kolay toz keki salınımı, daha düşük temizleme enerjisi maliyeti ve yüzey filtreleme özellikleri nedeniyle daha yüksek toplama verimliliği yer alır.

For More Information

Aokai Environtec is enthusiastic about helping customers achieve high and long-lasting filtration efficiency. This is exactly why we insist on manufacturing filter media in-house. As a leading filter media manufacturer and supplier, we custom design and manufacture dust filter media that best suits customers’ unique dust collection requirements. Aokai provides filter media solutions for abrasive, corrosive, high-temperature, and explosive dust filtration, and specializes in dust collection processes in asphalt mixing, chemicals, cement, metals, power generation, waste-to-energy, renewable energy, woodworking, and many other demanding industries. Aokai ile iletişime geçin for more information about our Filtre Ortamı manufacturing process and product offerings.